Turning a system by 90º 3

[drodrig]

Hi there,

We have a load on a plate we want to turn by 90º. What is the best way to do this?

I thought about using gears. Here the general idea:

We have this grey plate in horizontal position:

We mount the load on the top (just a block to simplify the representation):

We attache four supporting plates (in blue) on the original plate to get closer to the center of gravity:

A frame (in pink) around the system connecting all blue plates is placed:

Two stands (in transparent colour) are installed:

Then comes a pillow block bearing on the stand and a spur gear which is attached to the pink frame (there was a square hole). The shaft is in the center of gravity

And finally a small gear with a cranked handle on the stand:

I didn't calculate anything yet. First validating the idea, this is the easiest way I came up with to turn this

What do you think?

 

[IRstuff]

It's a way; but is your CG in the 90-deg position the same as in the 0-degree position?

Why not just buy a motorized tilt stage?

https://www.alibaba.com/product-det...telligent-motorized-pan-tilt_60830957355.html

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[drodrig]

Hi,
Yes, the idea is having the rotating axis in the center of gravity (or as close as possible, since it is a very heterogeneous load, difficult to estimate).

There are also many cables and pipes under the grey plate, that's why we have the frame around.

I didn't mentioned but the weight is ca. 1 ton

thanks

 

[rb1957]

why pick it up (elevate it) ? why not pivot about the edge (ie, tip the box onto it's side) ?

another day in paradise, or is paradise one day closer ?

 

[mfgenggear]

Kindly please describe the mechanics a little better.
please show a pic of which direction it is to be rotated, maybe draw arrows?
X, Y, Z & C
rotate (turn)parallel axis or tilt?
what type of mechanism to lock in position,
that setup visually looks to weak to hold the load and tilt it.
but it's conceptual right?

maybe some thing as simple as to have large bushings and pull pins to lock in place to support
the loads, while it's tilting and when horizontal.
and a hand crank may not have enough torque to rotate it.

 

[IRstuff]

That's a bit of torque 167 ft*lbf; you'd need at least 20:1 gear ratio, assuming a 1-inch CG offset and an 8-in crank --> 5.6 ft*lbf

one rev per second --> 0.01 hp, ignoring mechanical losses.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[BUGGAR]

A screw jack wold b self-locking.

 

[BrianE22]

I'd consider using a self-locking worm gear set instead of the spur gears.

 

[rb1957]

is the box being placed on the dark grey plate ? or is the dark grey plate already under the box ??

how to remove the blue plates and the pink frame, after rotation ?

how is the dark plate attached to the box (now no longer supported by the ground) ?

another day in paradise, or is paradise one day closer ?

 

[drodrig]

Thank you all for the answers

There is a "delicate" content in the box, it has to be carefully turned. We can't pivot it on an edge.

Here a more complete picture:

We rotate around the x axis. The box is ca. 1x1x1 m3 (3.3x3.3x3.3 ft3)

As you mention, a worm drive self-locking is much better idea: a safe, soft moving turning.

First we mount the lower plate on some base, then we put the box (the box is a representation, there are many complex things inside). After that we assembly the turning setup around it.

This will be moved once per year or so. The final position is with the grey plate vertically. We start horizontally to ease the "box" mounting procedure

thanks

 

[LittleInch]

The biggest Issue I se eis a massive increase in load on the side of the box when vertical.

At horizontal, whatever weight or mysterious things are in this box is spread over your 1m x 1m gray plate. Once vertical all the weight looks like it will be spread over the size of one of your little blue plates as the blue plate is fixed to the grey plate. Also at certain angles there will be a lot of force on the bottom corner of the box between the blue plat and the grey plate.

And what stops is tipping out if the CoG is ever so slightly out of the axis?

Also the Cof G will need to be the entire assembly, plate, blue and pink bits plus the box. Difficult to see that being uniform.



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Also: If you get a response it's polite to respond to it.

 

[MintJulep]

Why do you need to do this?

What can you accomplish after rotating the thing?

You are designing a complicated and expensive thing for no stated purpose. Is it worth it? Is there another way to accomplish whatever your goal is?

 

[mfgenggear]

I am assuming there will be thrust bearings under the grey plate to reduce friction, then a worm gear set to slowly rotate in the x axis.
this would help with the center of gravity. a safety locking mechanism to help support and lock in place in addition to the worm gear drive.
and electric motor could be used to rotate, problem with worm gearing it would have to rotate in both directions,
I would stick with a spur gear with standard off the shelf products.

 

[drodrig]

There is a mounting and a working position. Mounting is horizontal, working is vertical. We have to come up with a system to make the change, even if it is expensive/complicated.

In principle I am thinking about rotating it by hand, it's just 90º and not often. The idea is using bearings to take the weight and allow the rotation. I like the worm drive idea because of the self-locking option, I am seeing not all worm drives are self-locking, we will need additional blocking elements

cheers,

 

[rb1957]

why can't you tip about an edge ?

you can control the rotation just as well as you rotate in the lifted position.

is the box not strong enough ? add a simple frame (of angles) to support the box.

why not "mount" the box in it's "working" position ? sure maybe harder to mount stuff in the box, but it's "swings and roundabouts".

another day in paradise, or is paradise one day closer ?

 

[Compositepro]

https://www.google.com/search?sxsrf...pAhVlU98KHbt9BnwQsAR6BAgGEAE&biw=1304&bih=644

 

[LittleInch]

Or use wires at each corner.lift it vertically off the floor then with wheels on each wire pull it flat. I'll draw it tomorrow.


Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[rb1957]

skyhooks any one ?

I'd pick it up at all 8 corners.

another day in paradise, or is paradise one day closer ?

 

[moon161]

There is a mounting and a working position. Mounting is horizontal, working is vertical. We have to come up with a system to make the change, even if it is expensive/complicated.

Don't come up with anything, buy a weld positioner.

https://youtu.be/TJQGAAMlddY

You can get them in any size from small to gigantic.

You could even drop a satellite off one if you forget someone undid the bolts

 

[drodrig]

Hi everyone,

I had a meeting with the rest of my group and presented them different ideas (the ones proposed here)

In the end the chosen option is the wormdrive solution.

I still will talk to the person in charge of the halls/cranes but it seems pretty final.

The parts inside are very delicated so we feel safer with this solution

thanks all for the nice ideas!